Re: [PSUBS-MAILIST] Gasses from batteries

["Gary R. Boucher" <protek@shreve.net>]

Hydrocap (assuming that they are still there and functioning) in Miami
have caps that use a recombination element to combine the H and O
together to make water which drains back down into the battery. 
They are about $6.00 each and well worth it.  When batteries sit or
have a drain placed on them they also give off both hydrogen and oxygen
but in much smaller quantities.  You can use the caps to denote when
the charge begins to reach completion as they get warmer due to increased
recombination.  I have thought of gluing a sensor onto each cap to
monitor battery condition.  Such temperature sensors are cheap but
would require wiring attachments and a multiplexer to monitor all the
cells.

G. Boucher

At 06:21 PM 5/23/01, you wrote:
> Very true
> and acurate Ken
> Herve
>   
> > ----- Original Message ----- 
> > From: Subscuba@aol.com 
> > To: personal_submersibles@psubs.org 
> > Sent: Wednesday, May 23, 2001 8:56 PM
> > Subject: Re: [PSUBS-MAILIST] Gasses from batteries
> >
> > David, 
> >
> > For what it's worth: 
> >
> > During overcharge the electrolyte composed of a dilute solution of sulfuric 
> > acid decomposes this electrolyte and gives off Oxygen at one plate and 
> > Hydrogen at the other plate. The escaping gases also carry off small traces 
> > of the sulfuric acid which is mostly what you smell. 
> >
> > The bad thing for a sub is that these gases Hydrogen and Oxygen form an 
> > explosive mixture which when ignited go boom or in the case of the Shuttle 
> > give propulsion. Cases where lead acid batteries go boom is when the 
> > batteries are being overcharged and then a surge is drawn from the battery 
> > which can cause sparks with bad connections or degraded battery current 
> > conductors. This can and does happen when automotive batteries go bang. 
> >
> > Good luck, 
> >
> > Ken Martindale